# Inspect Email File

`POST https://api.getprospect.com/v2/email-verifications/inspect`

Read the head of an uploaded file to pick its email column before creating a bulk verification. Free: no credits. Answers the headers, up to 5 preview rows, the delimiter, the encoding, whether the first row is a header, and the columns that hold email addresses (best first). Nothing is stored.

> **How are credits spent?**
>
> Free. Nothing is stored.

## When to use it

Call it on an uploaded file before [Create Email Verification](https://getprospect.com/api-docs/email-verifications-create.md)
to see the file's headers, up to 5 preview rows, its delimiter and encoding, whether the first row is a
header, and which columns hold email addresses (best first in `email_column_candidates`, with
`suggested_email_column`).

`data.file_key` must be a file uploaded to your own workspace: a key uploaded by another workspace
answers `403`. Uploading a file through the API is not public yet, so today the key comes from a file
uploaded in the app. To verify a list from the API, send the addresses in `data.emails` to
[Create Email Verification](https://getprospect.com/api-docs/email-verifications-create.md).


## Authentication

Pass your API key in the `x-api-key` header.

## Body parameters

- `data` (object, required): The uploaded file to read.
  - `file_key` (string, required, max length: 512): The key of a file uploaded to your workspace (an App upload today: API uploads are not public yet).

## Example request

```bash
curl --request POST \
  --url https://api.getprospect.com/v2/email-verifications/inspect \
  --header 'Content-Type: application/json' \
  --header 'x-api-key: YOUR_API_KEY' \
  --data '
{
  "data": {
    "file_key": "3f2b6c1e-8a4d-4f0e-9c7b-2d5e1a6f9b30.5d41402abc4b2a76b9719d911017c592.csv"
  }
}
'
```

## Response 200

The head of the file.

```json
{
  "success": true,
  "data": {
    "headers": [
      "First name",
      "Last name",
      "Email",
      "Company"
    ],
    "preview": [
      [
        "Emily",
        "Carter",
        "emily.carter.sample@intercom.com",
        "Intercom"
      ],
      [
        "Liam",
        "Novak",
        "liam.novak.sample@getprospect.com",
        "GetProspect"
      ]
    ],
    "delimiter": ",",
    "encoding": "utf-8",
    "has_header": true,
    "email_column_candidates": [
      {
        "index": 2,
        "header": "Email",
        "sample": "emily.carter.sample@intercom.com"
      }
    ],
    "suggested_email_column": 2
  },
  "metadata": {
    "timestamp": "2026-10-08T14:07:55.000Z"
  }
}
```

## Response 400

Invalid body (`VALIDATION_ERROR` with `payload.code`), or the file could not be read (`VALIDATION_ERROR`, no code).

```json
{
  "success": false,
  "data": null,
  "metadata": {
    "timestamp": "2026-10-08T14:07:55.000Z"
  },
  "errors": [
    {
      "name": "VALIDATION_ERROR",
      "message": "file_key must be a string",
      "payload": {
        "field": "data.file_key",
        "code": "wrong_type",
        "received_type": "undefined",
        "constraints": {
          "maxLength": "file_key must be shorter than or equal to 512 characters",
          "isString": "file_key must be a string"
        }
      }
    }
  ]
}
```

## Response 401

Missing, unknown or inactive credentials (`UNAUTHORIZED`).

## Response 403

The file belongs to another workspace (`FORBIDDEN`).

## Response 500

Unexpected server error.